Guidelines for trimming a plum tree
Prune your plum trees in the right season and with the right technique to encourage healthier growth, better fruit quality, and minimize the risk of silver leaf disease.
Timing is Key
The best time to prune plum trees is during the mid to late summer, specifically between July and September. This timing ensures that pruning wounds have six weeks or more of dry weather to heal before fungal spores can infect, reducing the risk of silver leaf disease [1][2].
The Right Technique
When pruning plum trees, it's essential to use thinning cuts that remove whole branches at their point of origin. This discourages excessive new growth and maintains a balanced tree shape [1].
Canopy Management
To keep your plum tree healthy and productive, remove interior overcrowded branches and vertical water sprouts. This opens the canopy, allowing good light into the center of the tree, which improves fruit production [1][3].
Sanitation
Promptly dispose of pruned material and any diseased or damaged fruit to reduce the spread of pathogens [1].
Protection
Some gardeners apply a 50/50 mix of white latex paint and water to new exposed branches to prevent sunburn and reduce stress on the tree after pruning [1].
Pruning Young Plum Trees
Young plum trees (up to three years old) should be lightly pruned in spring to create a 'bush' shape with an open center. Prune all of the branches back by about a third, cutting to just above a bud, and take side shoots back by one half [5].
Pruning Established Plum Trees
Established plum trees (more than three years old) can be pruned in summer to keep the tree manageable and allow fruit to ripen. Cut just above a bud and sloping away from it when pruning [5].
By following this method, you can encourage healthier growth, better fruit quality, and minimize the risk of silver leaf disease, a common fungal problem for stone fruits, including plums. Remember, pruning fruit trees encourages a good size and shape, keeps the tree productive, and removes dead and damaged wood. Happy pruning!
[1] The Royal Horticultural Society. (2021). Pruning Plum Trees. Retrieved from https://www.rhs.org.uk/advice/profile?pid=329
[2] Garden Myths. (2021). Silver Leaf Disease. Retrieved from https://www.gardenmyths.com/myths/silver-leaf-disease
[3] University of California Agriculture and Natural Resources. (2021). Pruning Stone Fruits: Plums, Apricots, and Peaches. Retrieved from https://ucanr.edu/sites/UCBGardenWeb/files/284022.pdf
[4] Cornell University. (2021). Silver Leaf Disease. Retrieved from https://blogs.cornell.edu/treefruitipm/silver-leaf-disease/
[5] Gardeners' World. (2021). How to Prune Plum Trees. Retrieved from https://www.bbc.co.uk/gardening/howto/plants/plum_trees_pruning
Incorporating home-and-garden practices, one can engage in gardening by pruning plum trees in the mid to late summer season, a period identified as reducing the risk of silver leaf disease. To maintain a balanced shape, it's recommended to use thinning cuts while pruning, which discourages excessive new growth.
